Highly efficient, ultra-compact, and ultra-broadband bidirectional vertical coupler based on spin-directional locking

Abstract

An ultra-compact and ultra-broadband polarization-selective bidirectional vertical coupler is proposed. The coupler is designed by coupling unique two-plane chiral π -shaped plasmonic nanoantennas on top of a silicon-on-insulator waveguide. By taking advantage of the spin-directional locking principle and coupled nanoantennas, a circularly polarized incident light can be coupled into a specific direction through the waveguide, depending on its spin. Based on the full-vectorial finite element method, for a beam radius of 0.53 µm, the coupler with a size of 1.07 × 0.5 µ m 2 provides maximum coupling efficiency and an extinction coefficient of − 6.9 d B and 16.9 dB across the telecommunication C to U bands, respectively, with a 2 dB bandwidth of > 160 n m . The proposed coupler has potential applications in telecommunications, vertical cross-chip communications, and quantum information processing.

Optical Reading of Nanoscale Magnetic Bits in an Integrated Photonic Platform

“…Due to the localized and enhanced electric field, the light-matter interaction within these nanostructures (plasmonic nanoantennas) gets boosted, which leads to an effectively larger cross-section of scattering and absorption powers of coupled nanoparticles. Nowadays, such unique features of plasmonic nanoantennas allow them to play a key role in addressing nanoscale elements in different areas such as telecommunication [6], [7] and biosensing [8], [9]. Hence, it has been anticipated that we can improve MO activity at the nanoscale based on magneto-plasmonic effects via incorporating plasmonic nanoantennas in our photonic device.…”

Integrated Hybrid Plasmonic-Photonic Device for All-Optical Switching and Reading of Spintronic Memory

“…The magnified light-matter interaction enables PNAs to enhance the scattering and absorption cross sections of coupled nanoparticles, improving their effective polarizability and absorbed energy density. Such characteristics have turned PNAs into key components in designing miniaturized photonic devices in a variety of applications, ranging from telecoms [27,28] to biosensing [29,30].…”